1. Field of the Invention
The present invention relates to a technique for obtaining trace data.
2. Description of the Related Art
For example, in communications between multiple communications devices performed via a communications network, failures sometimes occur. In order to investigate the flow of processing up to where the failure occurred, a method is known in which trace data is taken. For example, Japanese Patent Application Laid-open No. H8-286993 in the Official Gazette discloses a method in which internal trace information, which is taken during wrap-around in an area of a communications control program having a trace function, is removed to an area provided to each circuit, when a failure is detected after establishing the data link, thus securing information that can be investigated.
Incidentally, failures also occur in a SAN (Storage Area Network) environment where a RAID (Redundant Array of Independent Inexpensive Disks) system and multiple servers are connected via a fiber channel switch, for example. In this SAN environment, sometimes it is difficult to identify the cause of the failure that occurred. For this type of case, one can consider a method in which, for example, analyzers are set up between the server and the fiber channel switch, and between the fiber channel switch and the RAID system, and the environment is made the same as when the failure occurred, and when the same failure occurs again, the cause is ascertained based on the analysis results from the analyzers. However, in this method, it may be troublesome to configure the environment the same as when the failure occurred, and much time may be required until the cause is ascertained.
Such problems are not restricted to SAN environments, but may also be present in other communications environments.